The proposed collector comprises a number of panels constituting the base of the collector; pipes or hoses extending across the assembled base, all these elements being made of plastic, each panel having a number of longitudinal groove-like emplacements of substantially paraboloidal profile and nose-like projections at distances from one another within the said emplacements.
The pipe or hose conduits are held in the said emplacements, being clamped between one side of the groove-like emplacement and said projections, the said conduits being interconnected and provided with means for connection with a water supply and with means for connection with a body of water which has been heated while in said conduits.
The collector is connected in a conventional manner with a source of water to be heated and a pool.
Collectors with which this application deals are intended to supply warm water without heating it to such a degree as would be required in domestic establishments. In face, water to be used in swimming pools should have a temperature of about 35.degree. C while in domestic establishments water is required having a temperature between 60.degree. and 80.degree. C.